Thanks for your comments. You're right Dennis - they are a lot of work, but the results do make it worthwhile.
Next time, I'll spend some more time and capture a wider area and make sure I don't miss anything!
I captured the rille the night before also, but at high resolution (attached). It's interesting to see the same feature at different resolutions. The one attached was with the 5x powermate, the one above was with the 2x barlow.